Small Engines (Lawn Mowers, etc.): Replace Starter Housing Assembly on Blower/Vac, mulching blade, starter cord

Question
Make: Troy-bilt
Model: TB320BV

Hi,

The starter cord on my Troy-bilt blower vac became frayed and eventually snapped.  I purchased a new starter housing assembly (which contains a new cord) and am in the process of replacing the old one.  I had no problem getting the housing off of the unit, as well as the mulching blade.  However, before I can remove the old starter housing, there is one more nut that I can't seem to remove.  It is the 9/16" nut at the end of the crankshaft that the  mulching blade was attached to.  When I try to loosen it, it doesn't stay in a fixed position.  Instead, it turns the engine.  I'm not even sure if this nut is meant to be unscrewed or if it is supposed to be pried off.  Can you give me any tips on how to remove this nut so I can get the old starter housing off?

Thx,
-gary

Answer
You need either a small impact, that will take it right off without any other work.

Or you need to lock the piston.  You can do this either with a tool made just for doing this or if you're very careful you can use something like a long 1/4" extension or screwdriver.  Just remove the spark plug and stick the tool in the cylinder and bring the piston up against it.  Thanks, PK.